title: DeltaNp63 is essential for epidermal commitment of embryonic stem cells.
abstract: In vivo studies have demonstrated that p63 plays complex and pivotal roles in pluristratified squamous epithelial development, but its precise function and the nature of the isoform involved remain controversial. Here, we investigate the role of p63 in epithelial differentiation, using an in vitro ES cell model that mimics the early embryonic steps of epidermal development. We show that the DeltaNp63 isoform is activated soon after treatment with BMP-4, a morphogen required to commit differentiating ES cells from a neuroectodermal to an ectodermal cell fate. DeltaNp63 gene expression remains high during epithelial development. P63 loss of function drastically prevents ectodermal cells to commit to the K5/K14-positive stratified epithelial pathway while gain of function experiments show that DeltaNp63 allows this commitment. Interestingly, other epithelial cell fates are not affected, allowing the production of K5/K18-positive epithelial cells. Therefore, our results demonstrate that DeltaNp63 may be dispensable for some epithelial differentiation, but is necessary for the commitment of ES cells into K5/K14-positive squamous stratified epithelial cells.
authors.affiliation: INSERM, U898, Nice, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Medawar
authors.forename: Thierry
authors.initials: T
authors.lastname: Virolle
authors.forename: Philippe
authors.initials: P
authors.lastname: Rostagno
authors.forename: Stéphanie
authors.initials: S
authors.lastname: de la Forest-Divonne
authors.forename: Karen
authors.initials: K
authors.lastname: Gambaro
authors.forename: Matthieu
authors.initials: M
authors.lastname: Rouleau
authors.forename: Daniel
authors.initials: D
authors.lastname: Aberdam
mesh_terms: D000818:Animals; D055415:Bone Morphogenetic Protein 4 / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D053595:Embryonic Stem Cells / Q000166:cytology*; D000078404:Epidermal Cells; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
chemical_list: C525810:Bmp4 protein, mouse; D055415:Bone Morphogenetic Protein 4; D010750:Phosphoproteins; D015534:Trans-Activators; C486419:Trp63 protein, mouse